Valve gear



' May 20, 1930. I J. 5; KEEN 1,759,701

.VALVE GEAR Filed vSept. 26, 1929 3 Sheets-Sheet 1 J. S. KEEN May 20, 1930.

VALVE GEAR Filed Sept. 26, 1929 3 Sheets-Sheet 2 I/LL/ her-d577- cfiiz @5726 May 20, 1930.

J- S. KEEN VA GEAR 3 Sheets-Sheet 3 Filed Sept. 25. 1929 00/??? 3 Kae a Patented May 20,1930 I I 5 I a 1 UNITED. STATES PATENT QFFICE I JOHN s. k' nN, or PHILADELPHIA, PENNSYLVANIA I 'v Lv GEAR j i Application filed September 26, 1929. Serial No. 395,358.

U My invention relates to :ce'rtain improve position the cam 4 is the admission cam and ments in valve gears for reversingsteam enthe cam 3 the cut-off cam.

gines, for. which a patent was granted .to Loosely mounted on the shaft beyond the 'Arturo Gaprotti, on the-11th day of August, opposite end of the screw is an exhaust cam 5 1925, No. 1,549,712. r I 5, which is the'same as. that shown and de- 5' One object of my invention is to provide a scribed in the above-mentioned patent. This safetymeans for preventing the jamming of exhaust cam and its operating mechanism, the shifter straps and the sleeves of the valve forms-no part of the present invention.

. vgear'when in either of two extreme positions, i Mounted on'the driving screw 2 are two 1 10 so as to prevent breaking of parts and to sleeves 6 and 7, having. spiral grooves for the allow for shifting without undue friction. threads or splines of the screw 2. The sleeves Afurther object of the invention is. to 10- are driven by the screw but are free to be 'cate the stop devices within the box containmoved longitudinally thereon. Each sleeve ing the valve gear] I has an annular groove 8 in its periphery, in 1 And a still further 'objectist'o so design {which extends anannular tongue 9 on a shift- 65 the parts that the stops will'be on theouter ing strap. 10 isthe shifting strap for the portions of the valve shifter within the box, sleeve 6, and 1O is the shifting strap for the insuring the two sleeves being parallel when sleeve 7 The'shifting strap 10 has an eX- in their extreme positions. tended portion 11 at. each side, on which are l a "The-invention is particularly adapted for trunnions12, and the strap 10* has an ex- Fig. 1 is a plan View of the valve. gear, hearings in thebox Hand is'a'ctuat'ed by.

. 0- Fig;i3 is a transverse'section. onthe line tothe other as shown.

use in locomotive valve gears of the type tended portion 11 of greater length than above described, where the valve gear is re the portions 11, and on this portion are trunversedby power. 1 nions 12 I r v In the accompanying drawings: A reversing shaft 13 is adapted tosuitable illustrating my improvement, the cap plate any suitable mechanism operated from the of the box. being removed; cab of the locomotive.- At each end of the Fig, 2 i longitudinal section of v the'box, reversing shaft 13 is a pair of cranks 15- and the valve'ge arcasingbeing partly in section; 16,'one crank of each set being at an angle ,3-3,Fig. ;2; I i Connecting the crank 15 to the trunnion 'Fig. 4 is a perspective view of 'one of the 12 on th s rap 10 a e s 17 nd ec i g ,connectingrods, showing the improved stops; he cranks 16 with the trunnions 12 on the and strap 1O arerods 18.

' i Figs; 5fand6 are 'diagramsillustrating my Secured to the cam 3 are two rods 19-19,

sh'aft1, which rotates at the same speed as length than the other and extends through invention in full forward and full reverse which are parallel withthe shaft'l. Both I po iti n re ectively rods extend through slots in the cam th rough The valve gearof the patent mentioned the holes in the sleeve 6 and through slots in above consists of-a distribution power driven the'sleeve 7. One of the rods is of greater I the driving axle of the locomotive. On this I a slot in the-exhaust cam 5. shaftIl' is a quick pitch driving screw 2, hav- Secured to the cam 4 are two rods 20-20, ing a multiple thread in the presentinstance, whichextend through slots in the sleeve-6 and which 'forms' spiral splines; Loosely mountthrough holes in the sleeve 7. .One of the ed on the shaft, beyond one end ofthe screw, rods extends through a slot in the exhaust are two cams 321ml 4. The cam 3 serves only cam 5 and with therod 19, serves to control to control the opening of the admission passaid'exhaust cam to a limited extent.

sage-ways when the-engine is running for- It will be understood that the cam 3 is the, jw'ard, and the oam 4 controls the cut-off of, inlet cam and the cam 4 is the cut-off when the same passagewayand when in the reverse the locomotive is going forward. When the valvegear is reversed the .cani'4 isthe inlet cam and the cam 3 is'cut'off, and these two '1 cams control the movement of the exhaust'to a certain extent. 7 I V I g Byvtheaabove arran ementvit will be seen that thecam 3 is adjusted to secure a certain .lead and the cam 4 is adjusted .fora certain cut off, when going forward.:: This. isi-accomplished by the sleeves 6 and 7'and the rods '19 -19 and 20-209." ,7 e V The cam 3 is adjusted by the sleeve; 5,

through the rods 19 19 and the cams is adjusted by the sleeve 7 through the rods '20 20 as fully described in the patentmentioned, above.

: When the sleeves are movedto full'forward position or to full reverse position; the sleeves tend vto jam, and excess frlction is exerted between the tongues'of a shifterand the wall 'ofthe slot in the sleeve. The main feature of my' invention'is to prevent this jammingand excesive friction, by providing means which will prevent the sleeves from coming in forcible contact when'the parts are in j t he present instance, withfth e extended 'por- '2 trunnions 12 either the full'forward or full .reverse positions fThis: I accomplish byprovidingthe connecting rods 17 with two lugs '21 and22,

one located atanangle to'the othe r'and oneprojecting slightly beyond the other. These lugsform stops" which come'vin'contact, in

,tions 11 of theshifter lo -on which are the By this arrangement the two shiftersjl0 10Iare held a 'ive'n distance a art atithe full forward or reverse position so that the'ton'gue' 9 on oneishifter w ill' belprevent'ed' from forcjthe' otherfshifter. V g V Y I lTlllSlIlVGYltlOH is particularlyusefulonlargelooomotwe's using power reverse mech in its sleeve a gainst-the sleeve controlled by anismfasit is difficult to stop the power re- .verseat a given point. Ina hand op'erated reverse, the hand can feel the contact and back off slightly if necessary, before damage yisdone; The "engine man cannot feel the contact through a power;reversemechanism before the damageis done.

WVhile the invention is particularly adapted foruse with power control mechanisnnit can be used to advantage on all forms of reverse -mechan1sm. r

' The peculiarity of the valve gear-as described in the above mentionedpatent isthat the shifters, when 1n the forward positiom'are further apart than when in'- the reverseposition; as shown in the diagram. I Consequently by 'the use-'of two lugs of different lengths 1 Claim a -ating cams connected to the sleeves. V QHThe combination in a valve gear; of a shaft having EL'SPIIZLl sphne thereon; two cams mechanism; rods 1. The combination in a valve gear having two sleeves mounted side-byeside, of a shifter on each sleeve; power means for turning the sleeves butsaid sleeves being capable .of adjustment longitudinally; a controlling shaft connected to the shifters of the-two sleeves; means for preventingtheja1nming' of the sleeves'and their shifters when ineither of the two extreme positions; and valve operloose on the shaft; two sleeves on'the splined and the other controlling "the other mm;

means for shifting the said isleeves longi tudinally on said shaft and stops preventing thesleeves from jamming whentheamech'a nism is in either of itstwo extreme positions.

3. The combination inia valve gear having portion of thezshafhone controlling onecam a power drivendistribution shaftyofia driving spiral spline thereon two .shiftingq'sleeves mounted on the splined portion of the shaft; so as to turn with said.splinedportionand capable of being 'movedlongitudinally with respect thereto; two cams; oneconnectedto one sleeve and the other connected to the other sleeve so that they 'can. be adj usted- 'on .said shaft; a shifter for each-sleeve reverse crank connectmg the crank mechanism wi-theach of saidshiftersrand 1 stopsifor limiting themovement of'the-shift? ers when in eitherof" the twoieX-treme posi- V r i tions, to prevent binding ofthe parts. 1

4:. The combination in a valveigeanl of a} power dr ven'shaft;havingia'screw orsplineportion thereon; two camslocated side-byside on said shaft beyondb one endbfithescrew; two slotted sleeves'on the screw and 7' arranged to turn with said screw but capable of being adjusted longitudinally thereon,-- one sleeve connectedflto one cam, the other sleeve connected to the .other cam .a shifter :for each sleeve in whichfthe sleeves areifree' to turn; a'double cranki'revers'e shaftprods at each side of the gear connectingthe cranks r to :their respective shifters and stops on f one'pair' 'of rods arranged tocome'incontact r -with the, shifter, to which the other pairiof rods is connected when'the fmechanism: is in its extreme positionf 5. The combinationin a'valve-gear,-'of a;

- power driven 'shaft;1a driving;screwithereon; two cams'located side-by-sideon said shaft beyond one end "of the'iscrew;-';*two' sleeves meshing with the screw and arranged to turn -with-said screw but capableof being ad uste'd longitudinally thereon, one:- sleeve connected to one cam, the other-sleevecom nected; to the other cam; a shifter on each" sleeve which the sleeve is free to turn rand v :a double'crank reverse-shaft, rodsat each "side of the gear connecting the cranks to' the v shifters, onei'set -o'f connectingrods-"which I are attached to one shijfter,1 having two steps" 7 mechanism. I

arranged to come in contactwith the shifter to which the other rods are connected, when 6. The combination in a valve gear, of a power driven shaft a driving screw thereon; two cams located side-by-side on said shaft beyond one end of the screw; two sleeves meshing with'the screw and arranged to turn with said screw but capable of being adjusted longitudinally thereon, one sleeve connected to one cam, the other sleeve connected to the other cam; a shifter on each sleeve in which the sleeve is free'to turn; a double crank reverse shaft having connecting rods at each side of "thegear, one rod being connected to one crank of the shaft and v to oneof the shifters, the other'rod being connected to the other crank and the other shifter; and two stops on one'set of rods,

Onestop being of'greaterlength than the other, so that when themechanism is in the V extreme forward position, the stop of greater length will prevent the parts jamming, and when in the extreme reverse position the shorter stop will prevent the parts jamming.

7. The combination H1 a valve gear having 7 a power driven reverseshaft; a driving screw thereon; two shifting sleeves'mountedon the v screw so as to turn with the screw and ca-V pable of being adjusted longitudinally thereon; two earns arrangedside-by-side, on said shaft, one cam being connected to one sleeve and the other cam being; connected to the other sleeve; a shifter oneach sleeve for controlling the position of its sleeve, each shifter having trunnions, the trunnions of one shifter extending beyond those of the other. shifter; a reversing shaft; a pair of cranks at each end of the shaft; rods connecting one set of cranks to the shifter having. the extended trunnions; rods connecting the cranks with the trunnions of the. other shifter; and lugs on the last-mentioned rods arranged to come in contact with the extended portions of the other shifter when the parts are in either oftheir two extreme positions. r i v JOHNS; KEEN.

in either of the two extremelpositionsofthe 

